Exercise before pregnancy attenuates the effects of prenatal stress in adult mice in a sex-dependent manner.

The present study aimed to investigate the long-term effects of exercise before pregnancy on changes induced by prenatal stress. Female and male Balb/c mice were divided into three groups: control (CON), prenatal restraint stress (PNS), and exercise before the gestational period plus PNS (EX + PNS). As adult, fear/anxiety behavior, corticosterone secretion, expression of hypothalamic-pituitary-adrenal (HPA)-related genes, as well as epigenetic modifications were evaluated. Exercise before gestation did not prevent the increased fear/anxiety behavior in PNS mice. A nearly significant (p = .06) basal corticosterone increase was observed in PNS males and the exercise before pregnancy reduced the stress-induced corticosterone increase in PNS females. In addition, an increase on prefrontal cortex (PFC) CRHR1 gene expression was observed in PNS females, which was attenuated by the exercise before gestation. We have also found a glucocorticoid receptor (GR) gene expression decrease in the prefrontal cortex in PNS males, as well as a histone H3 acetylation decrease (p = .06) close to the significance level. In conclusion, pregestational exercise may attenuate developmental changes induced by prenatal stress in a sex-dependent manner.